Selective photocatalytic reactions with organic photocatalysts
Selective photocatalytic reactions with organic photocatalysts
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DOI：
10.1039/c2sc21449k
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发表时间：
2013-01-01
期刊：
影响因子：
8.4
通讯作者：
Ohkubo, Kei
中科院分区：
文献类型：
--
作者：
Fukuzumi, Shunichi;Ohkubo, Kei
在可见光照射下，有机光催化剂通过光诱导电子转移反应与基质和分子氧实现了各种基质的选择性光催化氧化。光诱导电子从苯转移到3-氰基-1-甲基喹啉离子的单重激发态，使得苯被分子氧和水氧化，选择性地生成苯酚。在相同的实验条件下，用醇代替水得到烷氧基苯。芳香族化合物的光催化选择性氧化反应也已经实现，使用电子给体-受体连接的二联体，9-均三甲苯基-10-甲基吖啶离子（Acr（+）-Mes）作为光催化剂和分子氧作为氧化剂在可见光照射下。氧合反应通过分子内光诱导电子从均三甲苯部分转移到Acr（+）-Mes的吖啶鎓部分的单重激发态来引发，以提供极长寿命的电子转移状态。电子转移态可以分别氧化和还原底物和分子氧，导致底物的选择性氧化和卤化。通过使用Acr（+）-Mes作为光催化剂，也使得基材的C-C键形成成为可能。
Selective photocatalytic oxygenation of various substrates has been achieved using organic photocatalysts via photoinduced electron-transfer reactions of photocatalysts with substrates and dioxygen under visible light irradiation. Photoinduced electron transfer from benzene to the singlet-excited state of the 3-cyano-1-methylquinolinium ion has enabled the oxidation of benzene by dioxygen with water to yield phenol selectively. Alkoxybenzenes were obtained when water was replaced by alcohols under otherwise the same experimental conditions. Photocatalytic selective oxygenation reactions of aromatic compounds have also been achieved using an electron donor-acceptor linked dyad, 9-mesityl-10-methylacridinium ion (Acr(+)-Mes) acting as a photocatalyst and dioxygen as an oxidant under visible light irradiation. The oxygenation reaction is initiated by intramolecular photoinduced electron transfer from the mesitylene moiety to the singlet-excited state of the acridinium moiety of Acr(+)-Mes to afford an extremely long-lived electron-transfer state. The electron-transfer state can oxidize and reduce substrates and dioxygen, respectively, leading to selective oxygenation and halogenation of substrates. C-C bond formation of substrates has also been made possible by using Acr(+)-Mes as a photocatalyst.